move board slack constant, clarify comments

src/main/java/com/conveyal/r5/profile/FastRaptorWorker.java

@@ -55,12 +55,6 @@ public class FastRaptorWorker {
      */
     public static final int UNREACHED = Integer.MAX_VALUE;
 
-    /**
-     * Minimum time between alighting from one vehicle and boarding another, in seconds.
-     * TODO make this configurable, and use loop-transfers from transfers.txt.
-     */
-    public static final int BOARD_SLACK_SECONDS = 60;
-
     public static final int SECONDS_PER_MINUTE = 60;
 
     /**
@@ -70,8 +64,10 @@ public class FastRaptorWorker {
     private static final int DEPARTURE_STEP_SEC = 60;
 
     /**
-     * Minimum wait for boarding to account for schedule variation.
-     * FIXME clarify why this is separate from BOARD_SLACK. If it is not, merge the two constants into BOARD_SLACK_SEC.
+     * To be considered for boarding, a vehicle must depart at least this long after the rider arrives at the stop.
+     * Intuitively, "leave this long for transfers" to account for schedule variation or other unexpected variations.
+     * This is separate from BOARD_SLACK_SECONDS used in McRaptor and point-to-point searches, in case someone needs
+     * to set them independently.
      */
     private static final int MINIMUM_BOARD_WAIT_SEC = 60;
 

src/main/java/com/conveyal/r5/profile/PathWithTimes.java

@@ -19,6 +19,14 @@
  * A path that also includes itineraries and bounds for all possible trips on the paths (even those which may not be optimal)
  */
 public class PathWithTimes extends Path {
+
+    /**
+     * Minimum time between alighting from one vehicle and boarding another, in seconds.
+     * Appears to be used only in McRaptor and point-to-point searches.
+     * TODO make this configurable, and use loop-transfers from transfers.txt.
+     */
+    public static final int BOARD_SLACK_SECONDS = 60;
+
     /** Stats for the entire path */
     public Stats stats;
 
@@ -92,7 +100,7 @@ private void computeTimes (TransportNetwork network, ProfileRequest req, TIntInt
         // loop over departures within the time window
         // firstTrip is the trip on the first pattern
         int firstTrip = 0;
-        while (times[0][firstTrip][0] < req.fromTime + accessTime + FastRaptorWorker.BOARD_SLACK_SECONDS) firstTrip++;
+        while (times[0][firstTrip][0] < req.fromTime + accessTime + BOARD_SLACK_SECONDS) firstTrip++;
 
         // now interleave times
         double walkSpeedMillimetersPerSecond = req.walkSpeed * 1000;
@@ -137,7 +145,7 @@ private void computeTimes (TransportNetwork network, ProfileRequest req, TIntInt
 
                     // TODO should board slack be applied at the origin stop? Is this done in RaptorWorker?
                     // See also below in computeStatistics
-                    time = times[patIdx][trip][1] + transferTime + FastRaptorWorker.BOARD_SLACK_SECONDS;
+                    time = times[patIdx][trip][1] + transferTime + BOARD_SLACK_SECONDS;
                     itin.arriveAtBoardStopTimes[patIdx + 1] = time;
                 }
             }

src/main/java/com/conveyal/r5/profile/StatsCalculator.java

@@ -23,7 +23,7 @@ public static StatsCollection computeStatistics (ProfileRequest req, int accessT
 
         for (int start = req.fromTime; start < req.toTime; start += 60) {
             // TODO should board slack be applied at the origin stop? Is this done in RaptorWorker?
-            int timeAtOriginStop = start + accessTime + FastRaptorWorker.BOARD_SLACK_SECONDS;
+            int timeAtOriginStop = start + accessTime + PathWithTimes.BOARD_SLACK_SECONDS;
             int bestTimeAtDestinationStop = Integer.MAX_VALUE;
 
             PathWithTimes.Itinerary bestItinerary = null;